Activity: Qualitative analysis of Temporary Hardness of water sample. Share your observations and the reason for it.
Required materials: Two Aluminium Pots (easily available in kitchen), tap water, RO water, Gas Stove.
Activity:
Step 1: Take an aluminium pot and half fill with RO water and boil it for about 10-15 mins so that its volume gets reduced to half of its initial volume. Then, let it cool down.
Step 2: Take another aluminium pot and half fill with tap water and boil it for about 10-15 mins so that its volume gets reduced to half of its initial volume. Then, let it cool down also.
Observation: White precipitate in water will be stuck on the wall of the pot having tap water. While there will be comparatively no precipitate observed in the pot containing RO water.
Reason: White precipitate is carbonates of either Ca or Mg (cause of temporary hardness). Note: The amount of precipitate depends upon the hardness of the water sample.
chem XI Q9
